50 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 124 



and which has smooth lateral margins and a distolateral fringe of 

 setae. In the other three species the outer margin of the narrow 

 endopod is fringed completely with setae. The new species lacks the 

 longitudinal ventral carinae of the telson and the acute anterolateral 

 angles of the rostral plate that are characteristic of G. hendersoni. 



The broad uropodal endopod of this species will separate it from all 

 other species in the genus. 



Etymology. — The species is named for Alain Crosnier, who 

 collected the species and made available for study most of the other 

 material reported herein. 



Distribution. — Known only from Madagascar and the Comoro 

 Islands, in 50 m. 



Gonodactylus demanii Henderson, 1393 



Gonodactylus demani. — Gravier, 1935, p. 360, fig. 3. 



Gonodactylus De Manx. — Dollfus, 1938, p. 213 [part]. 



Gonodactylus demanii. — Manning, 1967b, p. 8, fig. 3 [older references]. 



Illustration. — Manning, 1967b, fig. 3. 



Previous records. — Fort Dauphin (Gravier, 1935); Maromandia 

 (Dollfus, 1938). 



Material. — 1 broken cf, CL 2.5; Tulear, Madagascar; from off- 

 shore reef; K. Boss; Anton Bruun Cruise 7, IIOE; USNM. 



Diagnosis. — Anterolateral angles of rostral plate rounded or 

 angled; ocular scales small; telson with 3 pairs of well-developed 

 marginal teeth, submedians with movable apices; dorsal surface of 

 telson with numerous spinules and tubercles; inner margin of uropodal 

 exopod smooth, lacking setae; most of inner margin of uropodal endo- 

 pod smooth, 1-5 proximal setae present; submedian teeth of telson 

 each with 1 ventral carina. 



Color. — Faded. 



Discussion. — As shown by Manning (1967b), G. demanii is the 

 western Indian Ocean counterpart of G. hendersoni Manning; it 

 differs from the latter in having more rounded anterolateral angles 

 on the rostral plate, 1-5 proximal setae on the uropodal endopod, 

 and in lacking sharp ventral carinae on both the submedian and inter- 

 mediate marginal teeth of the telson. Gonodactylus crosnieri, described 

 above, differs from both G. demanii and G. hendersoni in having a 

 broad, inflated uropodal endopod, with most of the inner and outer 

 margins lacking setae but a few distal setae present. 



Distribution.- — -Western Indian Ocean, from scattered localities 

 between southern India, the Red Sea, and northern Mozambique 

 (Manning, 1967b). 



